1. Field of Technology
The present invention generally relates to an apparatus for separating blood plasma and blood corpuscles from whole blood and, more particular, to the apparatus designed to be automatically primed.
In particular, the plasma filtration apparatus to which the present invention pertains comprises at least one plasma separator or filter for removing plasma from whole blood pumped from a patient, either human or animal, the remainder of the whole blood being subsequently returned to the patient after having been supplemented with an amount of physiologically compatible fluid substitute equal to the amount of the removed plasma.
2. (Description of the Prior Art)
Methods for treating a patient suffereing from kidney or liver failure or auto-immunization or the like disease are known. One such system employs a plasma separation method as well as an apparatus capable of performing the plasma separation wherein the whole blood extracted from the patient's artery is separated by a plasma separator or filter into blood plasma and blood corpuscles. The separated blood corpuscles are then returned to the patient's veins together with a physiologically compatible fluid substitute in a quantity sufficient to compensate for the reduction of the removed plasma.
According to the Japanese Laid-open Patent Publication No. 60-40302, there is disclosed the use of an additional plasma separator or filter for separating the blood plasma, which has been previously separated from the blood corpuscles in the manner as hereinabove described into a high molecular component containing various toxic substances and a low molecular component containing substances, such as, protein, useful to metabolism. In this case, the lower molecular component is returned to the patient together with the physiologically compatible fluid substitute in a quantity sufficient to compensate for the reduction of the removed high molecular component.
When using any of these prior art blood processing apparatuses thereof prior to the whole blood being processed during the clinical operation, the entire fluid circuit employed in the blood processing apparatus must be primed with physiological sodium chloride solution (normal saline solution) in order for the entire fluid circuit to be cleansed and to be rendered adaptable for the whole blood to be processed.
Hitherto, the priming procedure was carried out by disconnecting the plasma separator or separators from the fluid circuit and, after the disconnected plasma separator or separators were primed, connecting them to the fluid circuit components to complete the entire fluid circuit profile. Therefore, the priming procedure hitherto carried out was complicated and time-consuming, requiring the attendance of one or more skilled technicians. This was particularly true where two plasma separators or filters was employed such as in the apparatus disclosed in the above mentioned Japanese publication.